How to Start Sweet Pea Seeds

Nick the outer shell coating of each seed using a pair of fingernail clippers. Apply only enough pressure to crack or pierce the outer coating of the seed to facilitate a more rapid germination process. Soak the seeds in water overnight in lukewarm water.

Fill each 2-inch peat pot, to the top, with regular potting soil. Sow three seeds in each 2 inch peat pot, poking the seeds down into the potting mix to a depth of about one inch, and cover. Tamp the top layer of potting mix with a finger until just firm, without packing down too tightly. Water until the peat pot is damp, but not waterlogged, and set in a cool dark place for about 10 to 12 days.

Visit your peat pots after 10 days and observe closely to see if shoots have emerged above the soil. When the seedlings have emerged, transfer the seedling pots to a well-lit or sunny area with temperatures between 40 degrees and 55 degrees Fahrenheit. Maintain the temperature within this 15-degree range to prevent the need of a long hardening process when transplanting outdoors.

Provide an additional week or two for the seedlings to produce their first two leaves. When each has these first two leaves, thin the plants down leaving only one plant per peat pot.

Transplant your sweet pea plants as soon as the soil outdoors is workable and heavy frosts are over for the season. These plants enjoy a sunny location with partial shade during the hottest portion of the day, if possible to arrange. Otherwise, they will do fine in a sunny location only, though the blooms may be delayed by up to two weeks when the weather becomes hot.